Millimeter-wave (mmWave) communication is a promising solution to the current global shortage of bandwidth created by the rapidly growing demand for mobile data. While channel modeling and propagation characteristics for mmWave transmissions are fairly well understood, transient channel characteristics including how the hand of a human blocks antennas in a handset requires new, detailed research. Further, the impact and nature of interference in the face of mmWave directional beamforming are yet to be well explored. The key aspects of this proposal dealing with transient channel characterization and interference modeling will directly contribute to the realization of mmWave communications, which is envisioned not only for traditional fixed infrastructure cellular services but also for emerging, more prevalent, new service modes including unlicensed/licensed and mobile usage such as on buses, trains and cars, and peer to peer communications.
This proposal advances understanding in several fundamental aspects of mmWave communications. First, the proposal characterizes transient physical effects in mmWave channels such as fading due to human hand, head and body placement when holding phones. This characterization will be carried out with extensive measurements using directional antennas and novel modeling methodology employing finite-state Markov models. These transient channel models will then be integrated into the open-source measurement-based channel simulation platform NYUSIM, which generates realistic mmWave channel impulse responses under a wide range of practical settings. Second, the proposal provides analytical models of the interference distribution in a mmWave cellular system employing beamforming, including explicit probability density functions for the interference power at each receiving antenna element and interference correlation between different antenna elements as well as correlation between interference signals and intended signals. These distributions are parameterized and heavy-tailed in order to capture the large fluctuation in mmWave signals due to strong shadowing and a high probability of NLOS propagation in typical mmWave applications of dense environments. The interference models are verified by comparing with a system simulation using stochastic geometry to model locations of users and base stations and using NUYSIM to generate realistic mmWave channels among all nodes. The proposed research integrates measurement, modeling, theory, and analysis to advance fundamental understanding of mmWave communications, providing a means towards designing and evaluating mmWave communication systems.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
